The log flag enables the basic input/output system (BIOS) to log load events during loader execution. This logging is useful when the 7318 is not downloading. In addition, system administrators can use the logging feature to diagnose LAN problems that may not be directly caused by the 7318. A request for the BIOS console automatically enables logging.
The BIOS has three major logging phases: discover, BOOTP, and TFTP.
The discover phase of the network load determines basic network information about available hosts and routers on the network and potentially determines the load host. The discover phase follows and logs a three-step process:
#> load Probing for an IPX load host IPX load host named levesconte responded (00000011) IPX load host named lester responded (00000001)
Attempting to resolve IPX addresses Resolved IPX address: 00000011 at ethernet address 02608C2F15D9 Resolved IPX address: 00000001 at ethernet address 02608C2EB396
Netloader - DISCOVER 5.0 Using the AUI interface Probing for an IPX load host IPX external network is 00000002 IPX load host named muc2CNSLOADHOST responded (00000001) Resolved IPX address: 00000001 at ethernet address 02608C2EB87D Sending SAP advertisement (we are: CNS00406E0002DB_FFFFFFFF_BT)
Note: In the case of a User Datagram Protocol (UDP) load, the discover phase has no function. In a mixed load, the discover phase runs; however, UDP interaction only takes place in the BOOTP phase.
If there are problems in loading a 7318, the discover phase can be useful in problem determination. The determination of the Internet Packet Exchange (IPX) network number must happen; if it doesn't, the 7318 is not properly cabled to the LAN, or there are no IPX hosts sending packets on the network.
If the network is communicating and there are IPX hosts, there should be at least one response to the probe for a load host. While this response does not guarantee a download, it is necessary for the download process to progress. Also, after the 7318 has sent its SAP advertisement, you should be able to run the cnsview explore command from the host and see that particular 7318 in the list.
The discover phase handles the preliminary steps of finding an IPX load host, unless one is specified by the set host1 or set host2 command. In the latter case, the discover phase resolves the preconfigured addresses to communicate with the host.
The BOOTP phase is used to determine if the host can download that 7318. For a UDP load, this is the first active phase, since the discover phase is not used for a UDP load. For the BOOTP phase to operate correctly, the following must be true:
If the above criteria are met, the load host responds to the BOOTP request. If the BOOTP request file is null, the BOOTP response specifies the correct file to download. In the UDP download, the BOOTP packet may also have other IP information.
If the BOOTP phase does not get a response, but the discover phase has completed successfully, the host may not have been configured properly, or an incorrect file may have been specified. The BOOTP phase generates a trace similar to the following:
NetLoader - BOOTP 5.0 using IPX Request file from: levesconte Received BOOTP reply Download file is /usr/lib/cns/cns-s20
If the BOOTP phase completes successfully and a load host replies, it is likely that the TFTP phase will complete successfully. If the TFTP request is not honored, there may be a problem with the host. If the file transfer does not complete, there may be a problem with transmission on the Ethernet. The TFTP phase sends a packet similar to the following:
NetLoader - TFTP 5.0 using IPX Request download of /usr/lib/cns/cns-s20 from: 00000011:000000000001:83A2 Loading VERSION_3.44.1 in format: 5.12 uncompressed
Last block: 2418 Attempt to load config file: /usr/lib/cns/00406e0002db.cfg Request download of /usr/lib/cns/00406e0002db.cfg from: 00000011:000000000001:83A2 Last block: 65